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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Roger_S on May 04, 2008, 07:17:47 PM

Title: Blizzard 1230IV Internal SCS device connections
Post by: Roger_S on May 04, 2008, 07:17:47 PM

Hi all,

I have towered my miggy and I want to connect my hd and dvdrom (both scsi)  to my 1230 scsi device. both device are 68 pins, but the connection to the controller is a 25 pins external connector.

I it just that I need a convertor from 25 pins to 68? Or am i missing something?

Title: Re: Blizzard 1230IV Internal SCS device connections
Post by: Boot_WB on May 05, 2008, 10:58:41 AM

Here (http://pinouts.ru/HD/ScsiExternalAmigaMac_pinout.shtml) is the pinout of the DB 25 scsi connector, and here (http://pinouts.ru/HD/ScsiInternal_pinout.shtml) is the pinout of the internal IDC 50-pin connector.

I think the easiest way for you would be to adapt a standard 50-pin scsi cable to connect to the Blizzard 25-pin header (using the pinouts supplied). Ensure that you connect the intermediate ground connectors - your Amiga will not blow up if you don't, but you may experience data corruption problems.

Then, use individual 50 - 68 pin adapters (like this (http://www.virtualinformation.com/ebay_images/68mto50m2.jpg))to connect your scsi devices.

68-pin cables tend to use single core wires, which will not work properly with the 25-pin IDC crimp connector (they are much narrower cables than the older 50-pin types). Although you could solder a connector onto the 68-pin cable, the result would probably be quite fragile.

Title: Re: Blizzard 1230IV Internal SCS device connections
Post by: leirbag28 on May 05, 2008, 01:22:02 PM

Glad I saw this post...........as I am having the same problem............but I need to connect the Blizzards SCSI to an 80 pin SCSI 160gb HD....seems like i have to go through alot of adaptors?

if I just connect the available adaptors...will they work?  I am going from 25pin to 50pin adaptor and from that to a 68pin/80pin adaptor wich I got on ebay.

Title: Re: Blizzard 1230IV Internal SCS device connections
Post by: Boot_WB on May 05, 2008, 01:34:20 PM

Assuming the drive can operate in single-ended mode, it should work (as you say, a lot of adapters though!). You can get 50>80 pin adapters, which would cut down the adapter chain a bit at least.
My experience with 68>80 pin adapters was not good though, poor contact with the 80-pin SCA connection of the hard drive - the hard drive kept dropping out. Cheapo adapters!

There's usually a "force single-ended mode" jumper (usually marked SE), I'd recommend you set that. And, of course, you'll have to set the scsi ID in the 0-7 range, as scsi-2 only has 3 ID bits (0-7).